One kind of a liquid type hydroxylamine salt and an ionic-step synthesis of cyclohexanone caprolactam

The present invention is a method of cyclohexanone and hydroxylamine salt ionic liquid type direct synthesis of caprolactam, the method comprising the steps of: cyclohexanone, ionic liquid catalyst type hydroxylamine salt and zinc salt added to the reactor, stir at room temperature then in a closed system, the reaction at 140 ~ 160 ℃ 0.5 ~ 2.5h, caprolactam product was obtained; material ratio is the molar ratio of cyclohexanone: ionic liquid hydroxylamine salt: zinc = 1: 1 ~ 2: 1.5 ~ 3; wherein the ionic liquid is 1-sulfo-type hydroxylamine salt butyl-3-methylimidazolium hydrogen sulphate ionic liquid type hydroxylamine salt. The present invention will cyclohexanone oximation, and cyclohexanone oxime rearrangement in two steps, to achieve integration in the same reactor, thereby shortening the reaction scheme, significant savings in the cost of production of caprolactam, and has no equipment corrosion and environment-friendly and other advantages, to meet the requirements of green chemistry, conversion and selectivity of caprolactam cyclohexanone is very high, it can reach up to 100% and 91.0%.